Swivel chair



FIG. 1 is a perspective view of a swivel chair showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof with the bottom base rotated;

FIG. 4 is a left side view thereof with the bottom base rotated;

FIG. 5 is a right side view thereof with the bottom base rotated; and,

FIG. 6 is a top view thereof.

A bottom view thereof is omitted since it does not contain ornamental features. The heavy broken line showing of stitch lines forms portions of the claimed design, while the light broken line showing of portions of the swivel chair forms no part of the claimed design. 

CLAIM The ornamental design for a swivel chair, as shown and described. 